SOLUTION: A=4b A-b=9

Question 387118: A=4b
A-b=9
Found 2 solutions by tara0066, stanbon:
Answer by tara0066(31) (Show Source): You can put this solution on YOUR website!
A=(4B) (A)-B=9
On this one substitution is the best way to go. You can plug in 4B from the first one into the second one, replacing the A.
(4B)-B=9 Simplify
3B=9 Divide by 3
B=3
Next, plug that value for B into one of the original equations to solve for A.
A=4(B)
A=4(3)
A=12
Your answer is (12,3)
This is the point that these two lines will cross.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A=4b
A-b=9
---
Substitute for "A" and solve for "b":
4b - b = 9
3b = 9
b = 3
----
Since A = 4b, A = 4*3 = 12
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cheers,
Stan H.
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